Electric hoist structure



July 11, 1950 E. TODD 2,514,563

ELECTRIC HOIST STRUCTURE Filed Sept. 21, 1946 35 274 40 ya-985E? I l INVENTOR. Z/ML 701w,

Patented July 11, 1950 UNITED PATENT OFFICE ELE'CTRIC"HOIST STRUCTURE Earl Todd, K'okomo, Indi, assignctto Aerl, Inc;, Indianapolis; vInd., a: corporation Application September 21, 1946'; Serial No. 698,514

t l-Claims.- 1,.

This invention relatesto' a portable hoist strueture.

The chief object ofthis"invention is'to providea hoist structure which is comparatively simple; compact and'positive in operation both for elevating and lowering purposes and which may be of portable character and. which further may be of safety stop character.

The chief feature of the invention.- resides in electrically raising and lowering'a platform or the likeby means of a motor movable therewith, the platform and the like being. slidably associated with. a pair of spaced uprightsan'd'. the motor being operatively associated withanintermediate and parallel screw, the screw,. uprights. and the like comprisinga vertical. frame portion supported at its lower end bya. base which may or may not be of portable type, as desired.

Other objects and features of the invention will be set forth more fully hereinafter.

The fu l nature of the invention will be understood from the accompanying drawings and the following description and claims.

In the drawings:

Fig. 1 is a perspective view of a portable type embodiment of the invention.

Fig. 2 is a vertical sectional view of the vertical frame, the associated platform portion and the motor drive.

Fig. 3 is a top plan view of a bracket portion comprising the platform proper support and the motor proper support.

In Fig. 1 of the drawings ll) indicates a substantially U-shaped base structure which, at opposite ends of the arms, is provided with casters I l. A forwardly and medianly projecting tongue I?! rotatably supports a swiveling type caster l3 with which is associated a handle |4 so that the entire device is portable and can be moved from one location to another for transference of a load from one location to another.

Rigidly secured at their lower ends to the base ID are a pair of parallel tubes l5, and same may be suitably secured thereto by means of the bracket portion it which, intermediate the tubes, provides a hearing I! for an intermediate parallel screw Ill.

The upper ends of the tubes and the screw are suitab y connected together by the parallel upper bracket member [9. The screw is retained against rotation in the brackets l1 and [9 by any suitable means. Either carried by the base bracket IE or the base immediately adjacent thereto is 2. a down limit safety switch actuator 20-, as' desired;

Similarly the upper bracket" l9 may mount'an upper limit travel switch actuator structure 2|; Reference will be had 'thereto hereinafter.

'Preferably these actuators are of I the yielding pressure type so that when limit switches 'carried by the movab'le platform, hereinafter to be de scribed, are engaged at th'e uppermost elevation or the lowermost elevation, the electric motor, alsoto'bedescribed, is deenergized and automaticall'in'conditionsthe reverse circuit for motor reverse operation although the same is not effected 'znti-l =the'circuit is =manually closed by the opera tor; a's morefully pointed out hereinafter.

IniF'igsz- 2' and 3, more particularly," thereis illustrate-d a pair of vertically disposed spaced sleeves 22;.the same being rigidlyconnected to gether as at 23, and extending from the lower end of said sleeves is the laterally directed portion 24. Extending oppositely and substantially contemporaneously with the sleeves 22 is the base plate portion 25.

To the same is detachably mounted a motor 26, see Fig. 2, having upwardly directed shaft 21 carried by the rotor. The laterally disposed por' tion 24 may be of U-shaped form and may support a suitable platform arrangement, and this may be of any desired type or construction.

The central portion of the rigid connection 23 is preferably centrally apertured as at 28 to freely pass or accommodate the screw I 8. The tubular guides 22 obviously are slidably supported upon the tubular uprightslE.

Referring more particularly to Fig. 2, it will therein be noted that a housing structure is provided comprising the lower half portion 29 and an upper half portion 30, the same being suitably secured together as at 3|.

The lower portion 29 of this housing structure is centrally disposed between the two sleeves, as it were, although above the same. The housing includes a pair of aligned openings 32, the same freely passing the aforesaid screw I8.

In spaced relation thereto and in alignment with the motor shaft 21 is an opening 33 in the lower housing member 29. Rigid with the end of the shaft 21a, enclosed within the housing aforesaid, is a pinion gear 34. It is suitably supported by upper and lower anti-friction structures 35 and 36.

Interposed between the two openings 32 and in alignment therewith are the anti-friction structures 31 and 38 respectively, and interposed between these bearings is a nut structure 39 having an internal thread portion 40, the same having threaded engagement with the screw I8.

The exterior of this nut structure 39 includes the toothed arrangement 4|, the same meshing with the teeth of the pinion 34. Herein the pinion is smaller than the nut structure so that in efiect this direct drive from the motor to the nut structure is of speed reducing type.

The motor 26 is of reversible type and the nut and thread arrangement may be of self-locking character, as it were, or the meshing engagement between the pinion and the nut may be of helical:

type and thus may also be of reversible or selflocking character.

While the invention has been illustrated and I .nut means has a cooperating gear exterior meshing with that rotor shaft mounted gear.

described in great detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character.

The several modifications described herein as well as others which will readily suggest themselves to persons skilled in this art, all are considered to be within the broad scope of the invention, reference being had to the appended claims.

The invention claimed is:

1. In a hoist structure having a base, a frame means comprising a pair of substantially spaced, parallel, vertically disposed elongated guide members, means at the top connecting the guide members together, means at the bottom rigidly connecting the guide members together, and an elongated screw member similarly disposed therebetween and supported by said means at the opposite ends, the combination of platform means, elongated sleeves rigid therewith at one end of the platform means and slidable on said guide members, nut means rotatably supported by the platform means and supported thereby and hav- -3.'A hoist structure as defined by claim 1 wherein there is provided a housing rigid with the upper ends of the sleeves and a plurality of pairs'of vertically spaced anti-friction bearings are disposed in the housing, the pairs being laterally spaced, said housing having a pair of aligned openings registering with one pair of bearings and another opening registering with another pair of aligned bearings for the purpose described.

v EARL TODD.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Date Vallen vJune 12, 1945 

